Scientists have discovered a hidden 'death switch' in the brain that can trigger Alzheimer's disease. It is a toxic pairing of two proteins that, when combined, destroy brain cells and promote memory loss. Using a new compound, the researchers broke this pairing in mice. This slowed down the progression of the disease and protected brain cells. The compound also reduced the accumulation of the characteristic amyloid. The discovery points to a potential way to stop the destruction of neurons in the brain.